.lesson4{
  padding-top: 4rem;
  height: 100%;
  > div{
    height: 100%;
  }
}
.p-title{
  position: fixed;
  z-index: 3;
  height: 3.6rem;
  top: 80px;
  left: 260px;
  right: 0;
  border-bottom: 1px solid #eee;
  color: #FF6666;
  // margin: -1rem;
}

.btns{
  button{
    margin: 0.3rem;
  }
}